• 作者： 溫振源
• 作者服務機構： 國立臺灣大學醫學院解剖學科
• 中文摘要： 為確立楔狀核內脊神經背根終末與楔狀核一視丘投射神經原間之突觸關係，本實驗合併於大白鼠視丘腹底核注入過
  氧化氫?，以標出位在楔狀核內楔狀核一視丘投射神經原，同時於對側頸胸脊神經背根截斷，引起楔狀核內
  脊神經背根終末之實驗變性。結果顯示：(1)楔狀核一視丘投射神經原，估據楔狀核內神經細胞之大宗，估計至少有55%
  以上，此類神經原大小介於 18-30μm x 15-25μm之間，分佈於整個神經核內，而以核中段處最為密集。這些細胞呈圓
  形、橢圓、紡綞乃至多角形，胞質內具有相當發達的顆粒性內質網以及一般胞器，胞核或位中央或偏向一側，核膜都相
  當規則。過氧化氫?的反應顆粒，除分佈在胞體外，在較粗的樹突及軸突的起始節（initial segment）也都可發現；(2)脊
  神經背根終末的實驗變性，以增加電子密度型為主，另外絲絨性（flocculent）乃至顆粒性（granular）型也常見，唯神經
  絲增殖型(neurofilamentous hyperplasia)殊為少見，這些神經終末在楔狀核內，概以大型終末為主，並且含有圓形突觸
  泡，它與各種大小的樹突形成不對稱軸一樹突觸，本身又接受他種較小終末形成對稱軸一軸突觸，此種小型終末含有扁
  形或多樣形突觸泡；(3)在形態上證實脊神經背根終末與楔狀核一視丘投射神經原有直接突觸的關係存在，其於投射神經
  原形成突觸的位置，概在大中型樹突，形成不對稱軸一樹突觸。背根終末非但不與楔狀核一視丘投射神經原的胞體形成
  直接的軸一體突觸，也不與其他性質投射神經原或中間神經原的胞體有直接的突觸關係。至於背根終末與楔狀核一視丘
  投射神經原末梢樹突有無突觸關係，則未能確定，概因末梢樹突不易受過氧化氫?標示。g
• 英文摘要： In order to establish the synaptic relationship between the primary afferent terminals and thecuneothalamic relay neurons in the cuneate nucleus, the combined retrograde transport of horseradishperoxidase (HRP) and experimental degeneration have been applied in the young adult albino rats. 10 to30% HRP was injected contralaterally (0.5 μ1) in the ventrobasal thalamic nucleus and multiple dorsalrhizotomies (C5 to T1) in the cervicothoracic dorsal roots were performed on the side ipsilateral to thecuneate nucleus. The results showed that: (1) The cuneo-thalamic relay (CTN) neurons were the majorneuronal type of the nucleus. More than 55% of neurons have been labelled. These neurons were 18-30μm x 15-25 μm in sizes. They distributed in the whole rostrocaudal extent of the nucleus, particularlydense in the middle portion. The cells varied from round, oval, spindle to multipolar in shapes. They wererich in cytoplasmic organelles and had well-developed roughed endoplasmic reticulum. Their nucleus waseither centrally or eccentrically located and was rather regular. The HRP-positive granules were randomlydistribute in the perikaryon, dendrites and initial segment of the axons; (2) At least three types of theexperimental degeneration of the primary afferent terminals (PAT) were observed in the cuneate nucleustwo to three days after dorsal rhizotomy, namely, electron-dense, granular and neurofilamentous. ThesePAT were mostly large and contained round vesicles. They were commonly found within synaptic com-plex, in which they were presynaptic to dendrites of various sizes, and were themselves postsynaptic tosmaller axon terminals containing flattened vesicles. Degenerating PAT forming isolated synapses wereless commonly seen; (3) The PAT in the synaptic complex were directly presynaptic to the dendritesoriginating from the CTN neurons. The dendrites forming PAT-CTN synapese were of large and medium-sized. The PAT did not form direct axo-somatic synapses with the somata of CTN or of any other celltypes in the cuneate nucleus.
• 中文關鍵字： ventrobasal thalamic nucleus; cervicothoracic dorsal roots; cuneo-thalamic relay neuron; synaptic complex
• 英文關鍵字： --